昨天php上课学习了mysql数据库连接，再进行将sql语句结合，可以实现对数据库的增删改查

我简单的用php语言做了注册登录系统，其中嵌套了js的代码对数据进行筛选，注册部分页面以及代码如下

 

 register.php

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>register</title>
    <style type="text/css">
        .tab{
            color:Gray;
            font-size: 8px;
        }
    </style>
</head>
<body>
<form id="reg_form" action="register.php" method="post">
    <h1>注册信息</h1>
    <label for="username">用户名：</label>
    <input type="text" id="username" name="username"><sapn class="tab">（必填，3-15字符长度，支持汉字，字母，数字以及_）</sapn><br>
    <span id="username_err" style="display: none;color:red">信息不符合要求</span><br>

    <label for="password">密 码：</label>
    <input type="password" id="password" name="password"><span class="tab">（必填，不得少于6位）</span><br>
    <span id="password_err" style="display: none;color:red">信息不符合要求</span><br>

    <label for="rpassword">重复密码：</label>
    <input type="password" id="rpassword" name="rpassword"><br>
    <span id="rpassword_err" style="display: none;color:red">信息不符合要求</span><br>

    <label for="email">邮 箱：</label>
    <input type="text" id="email" name="email"><span class="tab">（必填）</span><br>
    <span id="email_err" style="display: none;color:red">信息不符合要求</span><br>
    <br>
    <span><input type="submit" value="提交注册"></span>
</form>
<script>
    //用户名
    var usernameInput = document.getElementById("username");
    usernameInput.onblur = checkUsername;

    function checkUsername() {
        var usernamevalue = username.value.trim();
        var reg=/^\w{3,15}$/;
        var flag = reg.test(usernamevalue);
        if (flag) {
            document.getElementById("username_err").style.display = 'none';
        } else {
            document.getElementById("username_err").style.display = '';
        }
        return(flag);
    }
    //密码
    var passwordInput = document.getElementById("password");
    passwordInput.onblur = checkPassword;

    function checkPassword() {
        var passwordvalue = password.value.trim();
        var reg=/^\w{6,12}$/;
        var flag = reg.test(passwordvalue);
        if (flag) {
            document.getElementById("password_err").style.display = 'none';
        } else {
            document.getElementById("password_err").style.display = '';
        }
        return (flag);
    }
    //重复密码
    var rpasswordInput = document.getElementById("rpassword");
    rpasswordInput.onblur = checkRpassword;

    function checkRpassword() {
        // var rpasswordvalue = rpassword.value.trim();
        var flag = passwordInput.value==rpasswordInput.value.trim();
        if(flag){
            document.getElementById("rpassword_err").style.display = 'none';
        }else{
            document.getElementById("rpassword_err").style.display = '';
        }
        return (flag);
    }
    //邮箱
    var emailInput = document.getElementById("email");
    emailInput.onblur = checkEmail;

    function checkEmail() {
        var emailvalue = emailInput.value.trim();
        var reg=/^[a-zA-Z0-9_.-]+@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*\.[a-zA-Z0-9]{2,6}$/;//判断邮箱是否正确
        var flag = reg.test(emailvalue);
        if (flag) {
            document.getElementById("email_err").style.display = 'none';
        } else {
            document.getElementById("email_err").style.display = '';
        }
        return (flag);
    }

    var regForm = document.getElementById("reg_form");
    regForm.onsubmit = function () {
        var flag = checkEmail() && checkPassword() && checkUsername();
        return flag;
    }
</script>

</body>
</html>



<?php

$con=mysqli_connect("localhost","root","123456","db_php1");
if (!$con)
{
    die('Could not connect: ' . mysql_error());
}
mysqli_select_db($con,"db_php1");

mysqli_set_charset($con,"UTF-8");

//session_start();
$username = $_POST["username"];
$password = $_POST["password"];
$email = $_POST["email"];

if($username && $password != '') {
    $sql_insert = "insert into user(username,password,email) values('$username','$password','$email')";
    mysqli_query($con, $sql_insert);
}
//$regdate = date("Y-m-d H:i:s");
//$result=mysqli_query($con,"select username from user where username = '$username'");
//
//$row=mysqli_fetch_assoc($result);

//print_r($row);

//echo "<hr/>";
//
//var_dump($row);
//if($username == $row['username']){
//
//    echo "<script>alert('用户名.$username.已经存在!请重新注册')</script>";}
//
//else{
    //用户名不存在 将注册的账号密码加入数据库


//    header('refrsh:3;url=login.html');
//    echo "<script>alert('$username.用户注册成功，请点击登录去登录!')</script>";
//}

mysqli_close($con);